The original script was written for Gene Hackman and Paul Newman before Peter Hyams decided to make the Hughes and Costanzo characters younger.
Gary Devore, the screen writer for this movie, disappeared in June 1997, while driving at night from Santa Fe, New Mexico to Santa Barbara, California, prompting an extensive search and media speculation. A year later, he and his car were discovered submerged below a bridge over the California Aqueduct near Palmdale, California off Highway 14. Devore was driving back from home. It is believed that Devore may have fallen asleep and drove into the aqueduct, however some conspiracy theories claim he was murdered.
A sequel titled "Still Running" was planned and different scripts were written. But Billy Crystal and Gregory Hines did not think any of them were strong enough to warrant a sequel and turned them all down.
Tom Selleck and John Travolta were also offered the roles of Hughes and Costanzo. Selleck turned it down due to commitments to Magnum, P.I. (1980) while Travolta's agent at that time, Michael Ovitz, felt that the project was wrong for him.
In several outdoor scenes, snow is simulated with foam.